History of the Peloponnesian War

As for the ambassadors who had gone at the time mentioned-after the taking of Plemyrium-from Syracuse to the cities, they had prevailed on them to join their side, and had raised and were just about to lead off the force, when Nicias, receiving early intelligence of it, sent to those of the Sicels who held the passes, and were in alliance with the Athenians, namely, the Centotripes, Alicyaeans, and some others, to beg them not to give free passage to the enemy, but to unite together and prevent their marching through their country, since there was no other by which they would attempt to do so, as the Acragantines would not grant them a passage through theirs.

When therefore the Siceliots were even on their march, the Sicels, in compliance with the request of the Athenians, laid an ambuscade for them in three different places, and falling upon them while off their guard and without any notice, killed about eight hundred of them, with all the ambassadors except one, namely, the Corinthian, who led to Syracuse those that had escaped, to the number of fifteen hundred.